sound/core/control_compat.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * compat ioctls for control API
   4  *
   5  *   Copyright (c) by Takashi Iwai <[email protected]>
   6  */
   7
   8 /* this file included from control.c */
   9
  10 #include <linux/compat.h>
  11 #include <linux/slab.h>
  12
  13 struct snd_ctl_elem_list32 {
  14         u32 offset;
  15         u32 space;
  16         u32 used;
  17         u32 count;
  18         u32 pids;
  19         unsigned char reserved[50];
  20 } /* don't set packed attribute here */;
  21
  22 static int snd_ctl_elem_list_compat(struct snd_card *card,
  23                                     struct snd_ctl_elem_list32 __user *data32)
  24 {
  25         struct snd_ctl_elem_list data = {};
  26         compat_caddr_t ptr;
  27         int err;
  28
  29         /* offset, space, used, count */
  30         if (copy_from_user(&data, data32, 4 * sizeof(u32)))
  31                 return -EFAULT;
  32         /* pids */
  33         if (get_user(ptr, &data32->pids))
  34                 return -EFAULT;
  35         data.pids = compat_ptr(ptr);
  36         err = snd_ctl_elem_list(card, &data);
  37         if (err < 0)
  38                 return err;
  39         /* copy the result */
  40         if (copy_to_user(data32, &data, 4 * sizeof(u32)))
  41                 return -EFAULT;
  42         return 0;
  43 }
  44
  45 /*
  46  * control element info
  47  * it uses union, so the things are not easy..
  48  */
  49
  50 struct snd_ctl_elem_info32 {
  51         struct snd_ctl_elem_id id; // the size of struct is same
  52         s32 type;
  53         u32 access;
  54         u32 count;
  55         s32 owner;
  56         union {
  57                 struct {
  58                         s32 min;
  59                         s32 max;
  60                         s32 step;
  61                 } integer;
  62                 struct {
  63                         u64 min;
  64                         u64 max;
  65                         u64 step;
  66                 } integer64;
  67                 struct {
  68                         u32 items;
  69                         u32 item;
  70                         char name[64];
  71                         u64 names_ptr;
  72                         u32 names_length;
  73                 } enumerated;
  74                 unsigned char reserved[128];
  75         } value;
  76         unsigned char reserved[64];
  77 } __packed;
  78
  79 static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
  80                                     struct snd_ctl_elem_info32 __user *data32)
  81 {
  82         struct snd_card *card = ctl->card;
  83         struct snd_ctl_elem_info *data __free(kfree) = NULL;
  84         int err;
  85
  86         data = kzalloc(sizeof(*data), GFP_KERNEL);
  87         if (! data)
  88                 return -ENOMEM;
  89
  90         /* copy id */
  91         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
  92                 return -EFAULT;
  93         /* we need to copy the item index.
  94          * hope this doesn't break anything..
  95          */
  96         if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
  97                 return -EFAULT;
  98
  99         err = snd_power_ref_and_wait(card);
 100         if (err < 0)
 101                 return err;
 102         err = snd_ctl_elem_info(ctl, data);
 103         snd_power_unref(card);
 104         if (err < 0)
 105                 return err;
 106         /* restore info to 32bit */
 107         /* id, type, access, count */
 108         if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 109             copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 110                 return -EFAULT;
 111         if (put_user(data->owner, &data32->owner))
 112                 return -EFAULT;
 113         switch (data->type) {
 114         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 115         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 116                 if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 117                     put_user(data->value.integer.max, &data32->value.integer.max) ||
 118                     put_user(data->value.integer.step, &data32->value.integer.step))
 119                         return -EFAULT;
 120                 break;
 121         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 122                 if (copy_to_user(&data32->value.integer64,
 123                                  &data->value.integer64,
 124                                  sizeof(data->value.integer64)))
 125                         return -EFAULT;
 126                 break;
 127         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 128                 if (copy_to_user(&data32->value.enumerated,
 129                                  &data->value.enumerated,
 130                                  sizeof(data->value.enumerated)))
 131                         return -EFAULT;
 132                 break;
 133         default:
 134                 break;
 135         }
 136         return 0;
 137 }
 138
 139 /* read / write */
 140 struct snd_ctl_elem_value32 {
 141         struct snd_ctl_elem_id id;
 142         unsigned int indirect;  /* bit-field causes misalignment */
 143         union {
 144                 s32 integer[128];
 145                 unsigned char data[512];
 146 #ifndef CONFIG_X86_64
 147                 s64 integer64[64];
 148 #endif
 149         } value;
 150         unsigned char reserved[128];
 151 };
 152
 153 #ifdef CONFIG_X86_X32_ABI
 154 /* x32 has a different alignment for 64bit values from ia32 */
 155 struct snd_ctl_elem_value_x32 {
 156         struct snd_ctl_elem_id id;
 157         unsigned int indirect;  /* bit-field causes misalignment */
 158         union {
 159                 s32 integer[128];
 160                 unsigned char data[512];
 161                 s64 integer64[64];
 162         } value;
 163         unsigned char reserved[128];
 164 };
 165 #endif /* CONFIG_X86_X32_ABI */
 166
 167 /* get the value type and count of the control */
 168 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
 169                         int *countp)
 170 {
 171         struct snd_kcontrol *kctl;
 172         struct snd_ctl_elem_info *info __free(kfree) = NULL;
 173         int err;
 174
 175         guard(rwsem_read)(&card->controls_rwsem);
 176         kctl = snd_ctl_find_id(card, id);
 177         if (!kctl)
 178                 return -ENOENT;
 179         info = kzalloc(sizeof(*info), GFP_KERNEL);
 180         if (info == NULL)
 181                 return -ENOMEM;
 182         info->id = *id;
 183         err = kctl->info(kctl, info);
 184         if (err >= 0) {
 185                 err = info->type;
 186                 *countp = info->count;
 187         }
 188         return err;
 189 }
 190
 191 static int get_elem_size(snd_ctl_elem_type_t type, int count)
 192 {
 193         switch (type) {
 194         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 195                 return sizeof(s64) * count;
 196         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 197                 return sizeof(int) * count;
 198         case SNDRV_CTL_ELEM_TYPE_BYTES:
 199                 return 512;
 200         case SNDRV_CTL_ELEM_TYPE_IEC958:
 201                 return sizeof(struct snd_aes_iec958);
 202         default:
 203                 return -1;
 204         }
 205 }
 206
 207 static int copy_ctl_value_from_user(struct snd_card *card,
 208                                     struct snd_ctl_elem_value *data,
 209                                     void __user *userdata,
 210                                     void __user *valuep,
 211                                     int *typep, int *countp)
 212 {
 213         struct snd_ctl_elem_value32 __user *data32 = userdata;
 214         int i, type, size;
 215         int count;
 216         unsigned int indirect;
 217
 218         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 219                 return -EFAULT;
 220         if (get_user(indirect, &data32->indirect))
 221                 return -EFAULT;
 222         if (indirect)
 223                 return -EINVAL;
 224         type = get_ctl_type(card, &data->id, &count);
 225         if (type < 0)
 226                 return type;
 227
 228         if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 229             type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
 230                 for (i = 0; i < count; i++) {
 231                         s32 __user *intp = valuep;
 232                         int val;
 233                         if (get_user(val, &intp[i]))
 234                                 return -EFAULT;
 235                         data->value.integer.value[i] = val;
 236                 }
 237         } else {
 238                 size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
 239                 if (size < 0) {
 240                         dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
 241                         return -EINVAL;
 242                 }
 243                 if (copy_from_user(data->value.bytes.data, valuep, size))
 244                         return -EFAULT;
 245         }
 246
 247         *typep = type;
 248         *countp = count;
 249         return 0;
 250 }
 251
 252 /* restore the value to 32bit */
 253 static int copy_ctl_value_to_user(void __user *userdata,
 254                                   void __user *valuep,
 255                                   struct snd_ctl_elem_value *data,
 256                                   int type, int count)
 257 {
 258         struct snd_ctl_elem_value32 __user *data32 = userdata;
 259         int i, size;
 260
 261         if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 262             type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
 263                 for (i = 0; i < count; i++) {
 264                         s32 __user *intp = valuep;
 265                         int val;
 266                         val = data->value.integer.value[i];
 267                         if (put_user(val, &intp[i]))
 268                                 return -EFAULT;
 269                 }
 270         } else {
 271                 size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
 272                 if (copy_to_user(valuep, data->value.bytes.data, size))
 273                         return -EFAULT;
 274         }
 275         if (copy_to_user(&data32->id, &data->id, sizeof(data32->id)))
 276                 return -EFAULT;
 277         return 0;
 278 }
 279
 280 static int __ctl_elem_read_user(struct snd_card *card,
 281                                 void __user *userdata, void __user *valuep)
 282 {
 283         struct snd_ctl_elem_value *data __free(kfree) = NULL;
 284         int err, type, count;
 285
 286         data = kzalloc(sizeof(*data), GFP_KERNEL);
 287         if (data == NULL)
 288                 return -ENOMEM;
 289
 290         err = copy_ctl_value_from_user(card, data, userdata, valuep,
 291                                        &type, &count);
 292         if (err < 0)
 293                 return err;
 294
 295         err = snd_ctl_elem_read(card, data);
 296         if (err < 0)
 297                 return err;
 298         return copy_ctl_value_to_user(userdata, valuep, data, type, count);
 299 }
 300
 301 static int ctl_elem_read_user(struct snd_card *card,
 302                               void __user *userdata, void __user *valuep)
 303 {
 304         int err;
 305
 306         err = snd_power_ref_and_wait(card);
 307         if (err < 0)
 308                 return err;
 309         err = __ctl_elem_read_user(card, userdata, valuep);
 310         snd_power_unref(card);
 311         return err;
 312 }
 313
 314 static int __ctl_elem_write_user(struct snd_ctl_file *file,
 315                                  void __user *userdata, void __user *valuep)
 316 {
 317         struct snd_ctl_elem_value *data __free(kfree) = NULL;
 318         struct snd_card *card = file->card;
 319         int err, type, count;
 320
 321         data = kzalloc(sizeof(*data), GFP_KERNEL);
 322         if (data == NULL)
 323                 return -ENOMEM;
 324
 325         err = copy_ctl_value_from_user(card, data, userdata, valuep,
 326                                        &type, &count);
 327         if (err < 0)
 328                 return err;
 329
 330         err = snd_ctl_elem_write(card, file, data);
 331         if (err < 0)
 332                 return err;
 333         return copy_ctl_value_to_user(userdata, valuep, data, type, count);
 334 }
 335
 336 static int ctl_elem_write_user(struct snd_ctl_file *file,
 337                                void __user *userdata, void __user *valuep)
 338 {
 339         struct snd_card *card = file->card;
 340         int err;
 341
 342         err = snd_power_ref_and_wait(card);
 343         if (err < 0)
 344                 return err;
 345         err = __ctl_elem_write_user(file, userdata, valuep);
 346         snd_power_unref(card);
 347         return err;
 348 }
 349
 350 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 351                                          struct snd_ctl_elem_value32 __user *data32)
 352 {
 353         return ctl_elem_read_user(card, data32, &data32->value);
 354 }
 355
 356 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 357                                           struct snd_ctl_elem_value32 __user *data32)
 358 {
 359         return ctl_elem_write_user(file, data32, &data32->value);
 360 }
 361
 362 #ifdef CONFIG_X86_X32_ABI
 363 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 364                                       struct snd_ctl_elem_value_x32 __user *data32)
 365 {
 366         return ctl_elem_read_user(card, data32, &data32->value);
 367 }
 368
 369 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 370                                        struct snd_ctl_elem_value_x32 __user *data32)
 371 {
 372         return ctl_elem_write_user(file, data32, &data32->value);
 373 }
 374 #endif /* CONFIG_X86_X32_ABI */
 375
 376 /* add or replace a user control */
 377 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 378                                    struct snd_ctl_elem_info32 __user *data32,
 379                                    int replace)
 380 {
 381         struct snd_ctl_elem_info *data __free(kfree) = NULL;
 382
 383         data = kzalloc(sizeof(*data), GFP_KERNEL);
 384         if (! data)
 385                 return -ENOMEM;
 386
 387         /* id, type, access, count */ \
 388         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 389             copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 390                 return -EFAULT;
 391         if (get_user(data->owner, &data32->owner))
 392                 return -EFAULT;
 393         switch (data->type) {
 394         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 395         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 396                 if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 397                     get_user(data->value.integer.max, &data32->value.integer.max) ||
 398                     get_user(data->value.integer.step, &data32->value.integer.step))
 399                         return -EFAULT;
 400                 break;
 401         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 402                 if (copy_from_user(&data->value.integer64,
 403                                    &data32->value.integer64,
 404                                    sizeof(data->value.integer64)))
 405                         return -EFAULT;
 406                 break;
 407         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 408                 if (copy_from_user(&data->value.enumerated,
 409                                    &data32->value.enumerated,
 410                                    sizeof(data->value.enumerated)))
 411                         return -EFAULT;
 412                 data->value.enumerated.names_ptr =
 413                         (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 414                 break;
 415         default:
 416                 break;
 417         }
 418         return snd_ctl_elem_add(file, data, replace);
 419 }
 420
 421 enum {
 422         SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 423         SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 424         SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 425         SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 426         SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 427         SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 428 #ifdef CONFIG_X86_X32_ABI
 429         SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 430         SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 431 #endif /* CONFIG_X86_X32_ABI */
 432 };
 433
 434 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 435 {
 436         struct snd_ctl_file *ctl;
 437         struct snd_kctl_ioctl *p;
 438         void __user *argp = compat_ptr(arg);
 439         int err;
 440
 441         ctl = file->private_data;
 442         if (snd_BUG_ON(!ctl || !ctl->card))
 443                 return -ENXIO;
 444
 445         switch (cmd) {
 446         case SNDRV_CTL_IOCTL_PVERSION:
 447         case SNDRV_CTL_IOCTL_CARD_INFO:
 448         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 449         case SNDRV_CTL_IOCTL_POWER:
 450         case SNDRV_CTL_IOCTL_POWER_STATE:
 451         case SNDRV_CTL_IOCTL_ELEM_LOCK:
 452         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 453         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 454         case SNDRV_CTL_IOCTL_TLV_READ:
 455         case SNDRV_CTL_IOCTL_TLV_WRITE:
 456         case SNDRV_CTL_IOCTL_TLV_COMMAND:
 457                 return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 458         case SNDRV_CTL_IOCTL_ELEM_LIST32:
 459                 return snd_ctl_elem_list_compat(ctl->card, argp);
 460         case SNDRV_CTL_IOCTL_ELEM_INFO32:
 461                 return snd_ctl_elem_info_compat(ctl, argp);
 462         case SNDRV_CTL_IOCTL_ELEM_READ32:
 463                 return snd_ctl_elem_read_user_compat(ctl->card, argp);
 464         case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 465                 return snd_ctl_elem_write_user_compat(ctl, argp);
 466         case SNDRV_CTL_IOCTL_ELEM_ADD32:
 467                 return snd_ctl_elem_add_compat(ctl, argp, 0);
 468         case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 469                 return snd_ctl_elem_add_compat(ctl, argp, 1);
 470 #ifdef CONFIG_X86_X32_ABI
 471         case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 472                 return snd_ctl_elem_read_user_x32(ctl->card, argp);
 473         case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 474                 return snd_ctl_elem_write_user_x32(ctl, argp);
 475 #endif /* CONFIG_X86_X32_ABI */
 476         }
 477
 478         guard(rwsem_read)(&snd_ioctl_rwsem);
 479         list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 480                 if (p->fioctl) {
 481                         err = p->fioctl(ctl->card, ctl, cmd, arg);
 482                         if (err != -ENOIOCTLCMD)
 483                                 return err;
 484                 }
 485         }
 486         return -ENOIOCTLCMD;
 487 }